EP 1577564 B1 20080213 - Hydraulic control system for working machine
Title (en)
Hydraulic control system for working machine
Title (de)
Hydraulische Steuervorrichtung für Baumaschine
Title (fr)
Système de contrôle hydraulique pour engin de construction
Publication
Application
Priority
JP 2004078856 A 20040318
Abstract (en)
[origin: EP1577564A2] A hydraulic control system for a working machine according to the present invention includes a regulator control valve for controlling an operation of a pump regulator and a controller for sending a control signal for changing a discharge quantity of the pump to the regulator control valve in accordance with an operation amount of an operating means. On the basis of the control signal, a secondary pressure in the regulator control valve is fed to the pump regulator. This system further includes a fail-safe valve disposed in a control line joining the pump regulator and the regulator control valve. The fail-safe valve has an ordinary position for sending the secondary pressure to the pump regulator and a fail-safe position for sending an oil pressure from a path other than the regulator control valve to the pump regulator in such a manner that a predetermined discharge amount is ensured. The fail-safe valve is configured so as to switch from the ordinary position to the fail-safe position in accordance with a failure signal indicative of failure in the regulator control valve. According to this, while adopting an electronic control system for the pump, it is possible to continue a work even in the failed condition of the system.
IPC 8 full level
F15B 11/16 (2006.01); E02F 9/22 (2006.01); F04B 49/00 (2006.01); F04B 49/10 (2006.01); F04B 49/22 (2006.01); F15B 11/00 (2006.01); F15B 20/00 (2006.01)
CPC (source: EP US)
E02F 9/2235 (2013.01 - EP US); E02F 9/226 (2013.01 - EP US); E02F 9/2296 (2013.01 - EP US); F15B 20/004 (2013.01 - EP US)
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR
DOCDB simple family (publication)
EP 1577564 A2 20050921; EP 1577564 A3 20051228; EP 1577564 B1 20080213; AT E386214 T1 20080315; CN 100441786 C 20081210; CN 1670317 A 20050921; DE 602005004683 D1 20080327; DE 602005004683 T2 20080612; JP 2005265062 A 20050929; JP 4453411 B2 20100421; US 2005204912 A1 20050922; US 2008017022 A1 20080124; US 7284371 B2 20071023
DOCDB simple family (application)
EP 05102016 A 20050315; AT 05102016 T 20050315; CN 200510055150 A 20050317; DE 602005004683 T 20050315; JP 2004078856 A 20040318; US 7834005 A 20050314; US 82892007 A 20070726